Re: [homenet] Let's make in-home ULA presence a MUST !?

Ted Lemon <mellon@fugue.com> Tue, 14 October 2014 21:49 UTC

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From: Ted Lemon <mellon@fugue.com>
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Date: Tue, 14 Oct 2014 16:49:35 -0500
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To: James Woodyatt <jhw@nestlabs.com>
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Subject: Re: [homenet] Let's make in-home ULA presence a MUST !?
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On Oct 14, 2014, at 4:40 PM, James Woodyatt <jhw@nestlabs.com> wrote:
> Naturally, you deprecate one of them, but my concern is that they never expire if the objective is for a ULA prefix to be invariant. So how many times can a network join with others before it runs out of space for deprecated and redundant but unexpired and invariant ULA prefixes?

I don't think the objective is for the ULA prefix to be invariant.   It's for the availability of a ULA prefix to be dependable, and for flash renumbering to be avoided whenever possible.   So there's no problem with deprecating a ULA when you have two, and no need for the ULA to remain stable over long periods of time.

The reason to want there to always be a ULA is that if you use a GUA as a ULA, the life cycle of your home network numbering is out of your control, and in the hands of whoever gave you the GUA.   That's the only thing I think the ULA prefix has to do on a homenet: provide you with dependable, graceful homenet-local numbering.